The goal of these studies is to develop improved methods of diagnosis and treatment of the patient who has sustained brain trauma. The studies have 3 major aims. First, to develop methods to accurately describe injuries in terms of their anatomical loci and their severity; second, to characterize the natural history of specific injuries; third, to develop methods of treatment that are based upon rapid measurement of the physiological and biochemical abnormalities that have occurred. The application of electrophysiological, morphological, biochemical and radiological techniques to these goals are described. Measurement of the spatial distribution, severity, and time of course of development of abnormalities in electrocortical activity, intracranial pressure, cerebral blood flow, the size of the extracellular space, and the integrity of the blood-brain barrier form the basis of selecting therapy for particular injuries, at particular stages of their development. The therapeutic protocols used are based upon the concept of manipulation of a set of functions, using techniques of reduction of intracranial pressure, adjustment of cerebral perfusion pressure, and regulation of the chemical environment of the brain to return function toward normal levels. The patients entering the study are followed from the acute through the recovery phase so that the natural history of particular injuries and the effects of therapy can be determined. BIBLIOGRAPHIC REFERENCE: Grossman, R. Beyer, C., Kelly, P., and Haber, B.: Acetylcholine and related enzymes in human ventricular and subrachnoid fluids following brain injury. Neuroscience Abstracts, Volume 1, 5th Annual Meeting of the Society for Neuroscience, New York City, 1975, p. 325.